Sending and receiving email messages via a computer network such as the Internet has been known for a number of years. One widely used protocol for sending a receiving email messages is Simple Message Transfer Protocol (SMTP). SMTP is described in, for example, RFC 2821—Simple Mail Transfer Protocol, published by the Internet Society (2001), fully incorporated by reference herein in its entirety, and RFC 1123—Requirements for Internet Hosts—Application and Support, published by the Internet Society (1989), also fully incorporated by reference herein in its entirety. RFC 2821 and RFC 1123 are both also presently available on the World Wide Web from the faqs.org website. SMTP provides for the sender of an email message to specify the email addresses or addresses to which a mail message should be sent, e.g., in the “TO” field of an email message. SMTP further provides an “EXPN” command that allows for the specification of a distribution list stored on a mail server that includes a list of one or more addresses to which an email message should be sent.
Distribution lists and the like provide a convenient and efficient way to send e-mail messages to multiple recipients without having to provide a specific e-mail designation or address for each of the multiple recipients. However, the list of e-mail addresses in a distribution list often does not precisely match the list of recipients to whom a person sending an e-mail wishes to send the e-mail. For example, a distribution list in a corporate environment may include all persons working in a particular office. A sender wishing to invite persons in the office to a surprise party for one of the people working in the office would want to send an email message to everyone in the office except the guest of honor. Presently, such a sender would have to enter the name or email address of every person in the office except the guest of honor into the “TO” field of an email message. Entering such names or email addresses is cumbersome, time-consuming, and inefficient, particularly where the number of intended recipients is large. Further, particularly as the number of intended recipients grows, it is likely that the sender of an email message will inadvertently neglect to identify some of the intended recipients of an email message.
Accordingly, what is needed is a way for a sender to be able to specify recipients on a distribution list or other list of message recipients who should be excluded from receiving the message.